In oil well drilling operation, the drill consumes plenty power mainly by the winch, mud pump, top drive device and rotary table. In common drilling operation, one or more power sources are configured to the winch, mud pump, top drive device and rotary table of the drill for supplying average power. The one or more power sources can be diesel generator, gas generator or hybrid generator etc.
In operations like bit lifting (for example, if the bit is damaged, or when a bit replacement is required to fit the different rock formation, it is necessary for the winch to lift the drill pipe and the bit out of the well for bit replacement), the winch consumes much more power such that the power source needs to supply a peak power to the winch instantaneously. However, the existing power source fails to provide peak power instantaneously due to its slow response speed.
The first solution to the technical problem of slow response speed of the existing power source is to raise the output power of power source drastically in advance. For example, in the preparation condition of bit lifting, raise the output power of the power source drastically to the first peak power. Since the requisite power of the winch is still average power at the time, a load bank must be configured to consume the power difference between the power source output power and the requisite power of the winch by heat consumption to achieve energy conservation.
In the bit lifting condition, raise the power source output power instantaneously from the first peak power to the second peak power. The requisite power of the winch increases from the average power to the peak power instantaneously such that, the problem of slow power source response speed is solved.
However, the existing load bank comprises more than one mechanical switches and resistors, wherein the service life of such switches are relatively short and the resistors are excessive. Additionally, the mechanical switches are discrete so that, they fail to regulate the power consumption of the load bank continuously.
One of the solutions to the problem of the shorter service life of mechanical switches is to replace the switches with electronic ones. However, the electronic switches cannot be controlled by soft switching, which brings new problems of noise and harmonic wave.
In addition, the load bank can only consume the power by its resistors instead of supplying power.
The second solution to the technical problem of slow response speed of the existing power source is to redesign the power source to raise the response speed. However, the redesign of a power source with faster response speed is time-consuming, complicate and costly.